This has been fixed on 4chan's end and is no longer needed.

src/General/Main.coffee

@@ -82,7 +82,6 @@ Main =
 
     switch hostname
       when 'www.4chan.org'
-        $.onExists doc, 'body', false, -> $.addStyle Main.cssWWW
         Captcha.replace.init()
         return
       when 'sys.4chan.org'
@@ -365,8 +364,6 @@ Main =
 
   css: `<%= importCSS('font-awesome', 'style', 'yotsuba', 'yotsuba-b', 'futaba', 'burichan', 'tomorrow', 'photon', 'spooky') %>`
 
-  cssWWW: `<%= importCSS('www') %>`
-
   features: [
     ['Polyfill',                  Polyfill]
     ['Captcha Replacement',       Captcha.replace]

src/General/css/www.css

@@ -1,3 +0,0 @@
-#captcha-cnt {
-  height: auto;
-}